Fergus-
You hit it dead on.=C2- Most amateurs are glad to help and most also have
either a good VHF SWR bridge or an antenna scope.=C2- Sure beats buying
one.=C2- Also, they are usually experts at soldering those pesky BNC conn
ectors.=C2- As for the VOR antenna, I just went out to my plane and took
some measurements.=C2- Since the receive antenna is horizontally polarize
d, it looks to me like=C2- copper tape fastened to the roof immediatly in
front of, or behind, the doors would be an ideal location.=C2- As someon
e said, if the ends need to be bent, it is very minimal impact.=C2- You c
ould center feed it and run the coax forward through the overhead panel or
back and down a side of the fuselage.=C2- The tape is available from=C2
-AS for a very reasonable=C2-price.=C2- As far as toroids go, I would
n't bother.=C2-=C2-This orientation would put the signal you want broad
side of the antenna, which is exactly what you need.=C2- The VOR antenna
will be receive only, so if it is correctly tuned with a bridge, dipper, or
antenna scope when installed,=C2-it will be fine.=C2- To start with, t
he standard formula for VHF is (5904 * K) /Frequency in MHZ.=C2- K is a v
ariable based on the size of the conductor, for copper tape,=C2-I=C2-wo
uld use about .95.=C2- The answer is in inches .=C2- If it is receive o
nly, I don't think it would even be necessary to tune it, the formula shoul
d be clos e enough.=C2- The whole thing should be about a one hour projec
t.=C2-
Jim Puglise A-283 (K9CQ)=C2-=C2- =C2-=C2- =C2-
----- Original Message -----
From: "Fergus Kyle" <VE3LVO@rac.ca>
Sent: Tuesday, September 1, 2009 12:00:48 PM GMT -05:00 US/Canada Eastern
Subject: Europa-List: VOR antennas et all
Cheers,
=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-I note the level of discuss
ion about antennas rising again, so will
make my pitch for an alternative.........
=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-Being both, along with seve
ral others on net, I have found a strange
sameness in the two groups. Building planes and radios seem to attract
similar folk in that there's a certain camaraderie, helpfulness and
reasonableness to both groups. And, it appears that given the opportunity
each admires and is curious about the other. Even the regular meetings seem
to acquire the same atmosphere.
=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-Given that, I have always s
uggested a builder of aircraft who needs
advice or measuring in the radio line contact his/her local Amateur Radio
club and solicit a dash of help in citing or measuring the antenna, both th
e
Av VHF, Beacon, VOR and assorted accessory freqs. It might be surprising to
find hams outbidding each other to come, see your project - pick the
gray-haired samples as they have tried it all because they are forever
trying to string up temporary, emergency and strange aerials everywhere.
Such items as airborne IRLP, APRS and other facets might come up....
=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-Anyway, I'll go now....
Ferg
Europa Classic 914 CSprop
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